Area Forecast Discussion
Issued by NWS Twin Cities, MN

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FXUS63 KMPX 281805
AFDMPX

Area Forecast Discussion
National Weather Service Twin Cities/Chanhassen MN
105 PM CDT THU JUL 28 2016

.UPDATE...
Issued at 1249 PM CDT Thu Jul 28 2016

Updated to include 18z aviation discussion below.

&&

.SHORT TERM...(Today and tonight)
Issued at 430 AM CDT Thu Jul 28 2016

A rather gloomy day is in store for today, with low clouds
expected to stick around most of the day from south central into
eastern MN and western WI. In fact, no substantial clearing is
expected until overnight when skies should begin to clear out from
north to south, though that clearing looks to only come to roughly
the northern half of the MPX area. For the southern half of the
area, it will likely be well into Friday before clouds finally
break up. The reason for the gloominess is that we find ourselves
in a broad positively tilted trough with several weak disturbances
within it and we do not look to fully cleanse ourselves of this
trough until Sunday.

With clouds, it will also be cool and expect highs to only top out
in the upper 60s and lower 70s where low clouds dominate the
day, with some filtered sun allowing highs in the upper 70s to
around 80 out in western MN.

Besides the low clouds, southeast MN and adjoining portions of WI
will have to deal with on and off light rain showers and drizzle
through the day. This is the result of a weak h7 low that will be
drifting from NW WI toward SE MN today. This h7 low will interact
with an inverted trough at the surface that will be extending up
from La Crosse to the Twin Cities, which will aid in the
shower/drizzle development through the day. Forecast soundings
show moist adiabatic soundings and little instability and
reflectivity forecasts produced by the CAMs struggle to produce
any reflectivity above 50 dbz, so removed any thunder mention from
the forecast and stuck with just a chance of shower wording.

.LONG TERM...(Friday through Wednesday)
Issued at 430 AM CDT Thu Jul 28 2016

Friday and Saturday will feature more sunshine than today, so we
expect a slow warming trend through the weekend, but near climate
normals. The time/height cross sections of relative humidity from
the 29.00/06Z guidance show very little moisture through the depth
of the atmosphere after today and for at least the first half of
the weekend. Although - fair weather cumulus are likely given the
cooler temperatures at 850mb. More moisture and warmer temps begin
to advect into MN/WI on Sunday, but the deeper moisture and high
humidity doesn`t return until Mon-Tue when a surface low takes
shape in the Central Plains and locally we get a stronger S-SE
flow regime. The next notable chance for rain /potentially heavy/
looks to occur Monday night and Tuesday morning near a warm front
that will be stretched out across MN/WI. The GFS/ECMWF have
another wave passing through Wednesday night. Overall big
picture...a warm and moist pattern looks to be in play next week.

&&

.AVIATION...(For the 18Z TAFS through 18Z Friday afternoon)
Issued at 1249 PM CDT Thu Jul 28 2016

Low clouds which had been prevalent over much of the area, more so
over eastern MN into western WI, has finally shown signed of
lifting around the 28/18z initialization time. Have been able to
initialize all sites with MVFR or better ceilings, with only KEAU
possibly bouncing into IFR due to shallow showers around that
terminal. Otherwise, ceilings will continue to rise to VFR levels
through the afternoon hours then scatter out tonight through
tomorrow, resulting in just high FEW-SCT clouds. Winds will remain
generally ENE with speeds below 10 knots.

KMSP...Ceilings have finally risen above 1700 feet at
initialization time and will continue to improve through this
afternoon and evening. Possibly a sprinkle or light shower may
drift over the terminal this afternoon. Otherwise, no
precipitation is expected and conditions will remain VFR tonight
through tomorrow.

/OUTLOOK FOR KMSP/
Sat...VFR. Winds SE 5 kts.
Sun...VFR. Winds SE 5-10 kts.
Mon...Mainly VFR. Chance MVFR/TSRA late. Winds SE 5-10 kts.

&&

.MPX Watches/Warnings/Advisories...
WI...None.
MN...None.
&&

$$

UPDATE...JPC
SHORT TERM...MPG
LONG TERM...CLF
AVIATION...JPC



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